5675 results about "Projection image" patented technology

Optical systems such as image display systems include a freeform optical waveguide prism and a freeform compensation lens spaced therefrom by a gap of air or index cement. The compensation lens corrects for aberrations which the optical waveguide prism will introduce in light or images from an ambient real-world environment. The optical waveguide prism receives actively projected images at an entry location, and emits the projected images at an exit location after internally reflecting the images along an optical path therein. The image display system may include an image source and coupling optics. The approach permits design of an optical viewing device, for example in optical see-through HMDs, achieving an eyeglass-form appearance and a wide see-through field of view (FOV).

A method of estimating a position of a foreign object in the body, comprising: (a) providing a 3D data set of at least one blood vessel; (b) acquiring at least one 2D projection image of the vessel including the object; (c) registering the 2D projection image of the vessel to the 3D data set; and (d) using the registration to estimate a 3D position of said object restricted to be in a blood vessel, according to said 3D data set.

An interactive table has a display surface on which a physical object is disposed. A camera within the interactive table responds to infrared (IR) light reflected from the physical object enabling a location of the physical object on the display surface to be determined, so that the physical object appear part of a virtual environment displayed thereon. The physical object can be passive or active. An active object performs an active function, e.g., it can be self-propelled to move about on the display surface, or emit light or sound, or vibrate. The active object can be controlled by a user or the processor. The interactive table can project an image through a physical object on the display surface so the image appears part of the object. A virtual entity is preferably displayed at a position (and a size) to avoid visually interference with any physical object on the display surface.

Techniques are provided for generating three-dimensional images, such as may be used in mammography. In accordance with these techniques, projection images of an object of interest are acquired from different locations, such as by moving an X-ray source along an arbitrary imaging trajectory between emissions or by individually activating different X-ray sources located at different locations relative to the object of interest. The projection images may be reconstructed to generate a three-dimensional dataset representative of the object from which one or more volumes may be selected for visualization and display. Additional processing steps may occur throughout the image chain, such as for pre-processing the projection images or post-processing the three-dimensional dataset.

A method and system for acquiring, processing, storing, and displaying x-ray mammograms Mp tomosynthesis images Tr representative of breast slices, and x-ray tomosynthesis projection images Tp taken at different angles to a breast, where the Tr images are reconstructed from Tp images

A plurality of projection images are acquired over an angular range during the slow rotation of a C-arm gantry having a source and detector. Phase-specific reconstructions are generated from the plurality of projections, wherein each phase-specific reconstruction is generated generally from projections acquired at or near the respective phase. In one embodiment, a plurality of motion estimates are generated based upon the phase-specific reconstructions. One or more motion-corrected reconstructions may be generated using the respective motion estimates and projections. The motion-corrected reconstructions may be associated to form motion-corrected volume renderings.

A technique is provided for geometrical analysis and calibration of a volumetric imaging system. The technique includes computing a projection error between estimated locations of a set of markers of a phantom based on a estimated imaging geometry and observed locations of the respective markers for at least one projection image, decomposing the computed projection error into one or more error components corresponding to respective geometric parameters of the imaging geometry, and updating at least one parameter of the estimated imaging geometry based on the one or more error components.

A scanning method for scanning samples of biological cells using optical tomography includes preparing, acquiring, reconstructing and viewing three-dimensional images of cell samples. Concentration and enrichment of the cell sample follows. The cell sample is stained. Cells are isolated from the cell sample and purified. A cell/solvent mixture is injected into a gel by centrifugation. A cell/gel mixture is injected into a capillary tube until a cell appears centered in a field of view using a step flow method. An optical imaging system, such as a fixed or variable motion optical tomography system acquires a projection image. The sample is rotated about a tube axis to generate additional projections. Once image acquisition is completed, the acquired shawdowgrams or image projections are corrected for errors. A computer or other equivalent processor is used to compute filtered backprojection information for 3D reconstruction.

Aspects of the present invention relate to the projection of imagery from a head-worn computer, wherein a projector with x-y control and a laser are mounted in the head-worn computer and positioned to project a raster style interactive user interface image onto a nearby surface.

An autostereoscopic display and method of displaying multidimensional images involves a first lenticular array preferably of cylindrical lenses positioned between a viewer and a pixel array, and a second lenticular array also preferably of cylindrical lenses positioned between the first lenticular array and the viewer. The pixel array includes several pixel groups that project images through corresponding groups of first lenses within the first lenticular array. A pitch of the lenses within the second lenticular array differs from a pitch of the lenses in the first lens groups within the first lenticular array. The display can be manufactured or retrofit with the first and second lenticular arrays. By use of the first lenticular array, light from plural color pixels may be focussed to a single point so that color subpixels arranged in a direction transverse to the direction of the cylindrical lenses of the first lenticular array may be focussed to a single point on the secondary lenticular array and then as a single image to the user.

The invention provides improvements in reconstructive imaging of the type in which a volume is reconstructed from a series of measured projection images (or other two-dimensional representations) generated by projection of a point x-ray source (or other radiation source), positioned at a distinct focus, through the volume to a plane at which the respective projection image is acquired (“detector plane”). In one aspect, the improvements are with respect to back-projecting a two-dimensional representation lying in the detector plane (representing, for example, a difference between an originally-acquired measured projection image and a subsequently-generated estimate thereof) to generate three-dimensional representation (which can be used, for example, to update an estimate of the volume). According to this aspect, for each of one or more slices of the 3D representation parallel to the projection plane and for each distinct focus at which a projection is generated, the following steps are performed in connection with the back-projection: (i) warping the first 2D representation to generate a second 2D representation by applying to the first 2D representation a selected linear mapping, where that selected linear mapping would map, in order to match dimensions of the respective slice within the 3D representation, a region defined by projection, at the respective focus, of comers of that slice onto the detector plane, and (ii) incrementing values of each of one or more voxels of the respective slice by an amount that is a function of a value of a correspondingly indexed pixel of the second 2D representation. A related aspect provides improvements with respect to forward-projecting, as well as in iterative (and non-iterative) methodologies that incorporate both back-projection and forward-projection.

A method for determining a translation of a three-dimensional pre-operative image data set to obtain a registration of the three-dimensional image data with a patient positioned in a projection imaging system. In one embodiment the user identifies an initial three-dimensional organ center from projections and extreme contour landmark points of the object on a set of projections. A set of contour points for the image object in each of a plurality of three-dimensional cross-section planes; is obtained and the points projecting nearest to the user-identified landmark points are selected. A three-dimensional grid having a predetermined number of intervals at a predetermined interval spacing centered at the user-identified organ center is defined. The three-dimensional image data contour points as centered onto each grid point are projected for evaluation and selection of the grid point leading to contour points projecting nearest to the user-identified landmark points. This selection leads to the iterative definition of a series of improved estimated three-dimensional organ centers, and associated translation vectors. Registration of a three dimensional image data to the patient positioned in a projection imaging system will allow, among other things, overlay of a visual representation of a pre-operative image object onto a projection image plane that can serve as a visual tool and a surgical navigation aid. In particular, the position and orientation of a medical device can be shown with respect to the three-dimensional image data and thus enable quicker, safer, and less invasive navigation of the medical device to and within an organ of interest.

A 3D image acquisition apparatus comprises a pattern projection section which projects a pattern on an object to be measured, an imaging section which is disposed at a distance from the pattern projection section and images the object on which the pattern has been projected, and a depth calculation section which detects the projection pattern projected on the object on the basis of an image acquired by the imaging section, collates the detected pattern and the projected pattern, and calculates a depth of respective parts of the object on the basis of the correspondency of the collation. The projected pattern is stripes/matrix formed by alternately arranging areas with local maximum/minimum luminance values. Thus, stripes/matrix boundaries can be exactly extracted from the pattern projection image, and correct decoding is performed from the encoded projection image even where the object is not a white-based color one or a low-saturation color one.

A projection system uses a transformation matrix to transform a projection image p in such a manner so as to compensate for surface irregularities on a projection surface. The transformation matrix makes use of properties of light transport relating a projector to a camera. If the resolution a camera is lower than that of a projector within said projection system, then the transformation matrix will have holes where image data corresponding to a projector pixel will have been lost. In this, case, new image are generated to fill-in the holes.